package com.atguigu.gulimall.product.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.gulimall.product.service.CategoryBrandRelationService;
import com.atguigu.gulimall.product.vo.Catelog2Vo;
import org.apache.commons.lang3.StringUtils;
import org.redisson.Redisson;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.cache.annotation.Caching;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;

import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.Resource;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

//    @Autowired
//    CategoryDao categoryDao;
    @Resource
    CategoryBrandRelationService categoryBrandRelationService;

    @Autowired
    StringRedisTemplate redisTemplate;

    @Autowired
    RedissonClient redisson;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2.组装成父子的树形结构
        //2.1 找到所有一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
            categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildrens(menu,entities));
            return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort()==null?0:menu1.getSort())-(menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return level1Menus;
    }

    @Override
    public void removeMenuByIds(List<Long> catIds) {
        baseMapper.deleteBatchIds(catIds);
    }

    @Override
    public Long[] findCatelogPath(Long catelogId) {
        List<Long> path=new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, path);
        Collections.reverse(parentPath);
        return parentPath.toArray(new Long[parentPath.size()]);
    }

//    @Caching(evict = {
//            @CacheEvict(value = "category",key = "'getLevel1Categorys'"),
//            @CacheEvict(value = "category",key = "'getCatalogJson'")
//    })
    @CacheEvict(value = "category",allEntries = true)
    @CachePut//双鞋模式
    @Transactional
    @Override
    public void cascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(),category.getName());
        //同时修改缓存中的数据
        //redis.del("CatelogJson")
    }

    @Cacheable(value = {"category"},key = "#root.method.name",sync = true)
    @Override
    public List<CategoryEntity> getLevel1Categorys() {
        System.out.println("getLevel1Categorys...");
        List<CategoryEntity> categoryEntities = this.baseMapper.selectList(new QueryWrapper<CategoryEntity>().eq("parent_cid", 0));
        return categoryEntities;
    }

    @Cacheable(value = "category",key = "#root.method.name")
    @Override
    public Map<String, List<Catelog2Vo>> getCatalogJson() {
        System.out.println("查询了数据库。。。");
        List<CategoryEntity> selectList= baseMapper.selectList(null);
        //1.一级分类
        List<CategoryEntity> level1Categorys = getParent_cid(selectList,0L);
        //2.封装数据
        Map<String, List<Catelog2Vo>> parent_id = level1Categorys.stream().collect(Collectors.toMap(k -> k.getCatId().toString(), v -> {
            //3.每一个子类的二级分类
            List<CategoryEntity> categoryEntities = getParent_cid(selectList,v.getCatId());
            List<Catelog2Vo> catelog2Vos = null;
            if (categoryEntities != null) {
                catelog2Vos = categoryEntities.stream().map(l2 -> {
                    Catelog2Vo catelog2Vo = new Catelog2Vo(v.getCatId().toString(), null, l2.getCatId().toString(), l2.getName());
                    //查询三级分类
                    List<CategoryEntity> categoryLevel3 = getParent_cid(selectList,l2.getCatId());
                    if (categoryLevel3!=null){
                        //封装为指定格式
                        List<Catelog2Vo.Catelog3Vo> level3Catelogs = categoryLevel3.stream().map(l3 -> {
                            Catelog2Vo.Catelog3Vo catelog3Vo = new Catelog2Vo.Catelog3Vo(l2.getCatId().toString(),l3.getCatId().toString(),l3.getName());
                            return catelog3Vo;
                        }).collect(Collectors.toList());
                        catelog2Vo.setCatalog3List(level3Catelogs);
                    }
                    return catelog2Vo;
                }).collect(Collectors.toList());
            }
            return catelog2Vos;
        }));
        return parent_id;
    }


    public Map<String, List<Catelog2Vo>> getCatalogJson2() {
        //加入缓存
        String catalogJSON=redisTemplate.opsForValue().get("catalogJSON");
        if (StringUtils.isEmpty(catalogJSON)){
            System.out.println("缓存不命中。。。查询数据库。。。");
            Map<String, List<Catelog2Vo>> catalogJsonFromDb = getCatalogJsonFromDbWithRedisLock();
        }
        System.out.println("缓存命中。。。直接返回。。。");
        Map<String, List<Catelog2Vo>> result=JSON.parseObject(catalogJSON,new TypeReference<Map<String, List<Catelog2Vo>>>(){});
        return result;
    }

    public Map<String, List<Catelog2Vo>> getCatalogJsonFromDbWithRedissonLock() {
        RLock lock = redisson.getLock("CatalogJson-lock");
        lock.lock();
        Map<String, List<Catelog2Vo>> dataFromDb = null;
        try {
            dataFromDb = getDataFromDb();
            } finally {
            lock.unlock();
            }
            return dataFromDb;
    }

    public Map<String, List<Catelog2Vo>> getCatalogJsonFromDbWithRedisLock() {
            //占用分布式锁
        String uuid = UUID.randomUUID().toString();
        Boolean lock = redisTemplate.opsForValue().setIfAbsent("lock", uuid,300,TimeUnit.SECONDS);
        if (lock){
            System.out.println("获取分布式锁成功");
            //加锁成功，执行业务
            //设置过期时间,与加锁同步
//            redisTemplate.expire("lock",30,TimeUnit.SECONDS);

            Map<String, List<Catelog2Vo>> dataFromDb = null;
            try {
                dataFromDb = getDataFromDb();
            } finally {
                String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
                Long lock1 = redisTemplate.execute(new DefaultRedisScript<Long>(script, Long.class),
                        Arrays.asList("lock"),
                        uuid);
            }
//            redisTemplate.delete("lock");
            //获取值对比，对比成功删除，原子操作 lua脚本解锁
//            String lockValue = redisTemplate.opsForValue().get("lock");
//            if (uuid.equals(lockValue)){
//                redisTemplate.delete("lock");
//            }

            return dataFromDb;
        }else {
            //加锁失败，重试
            System.out.println("获取分布式锁失败，等待重试");
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            return getCatalogJsonFromDbWithRedisLock();//自旋的方式
        }



    }

    private Map<String, List<Catelog2Vo>> getDataFromDb() {
        String catalogJSON=redisTemplate.opsForValue().get("catalogJSON");
        if (!StringUtils.isEmpty(catalogJSON)){
            Map<String, List<Catelog2Vo>> result= JSON.parseObject(catalogJSON,new TypeReference<Map<String, List<Catelog2Vo>>>(){});
            return result;
        }
        System.out.println("查询了数据库。。。");
        List<CategoryEntity> selectList= baseMapper.selectList(null);
        //1.一级分类
        List<CategoryEntity> level1Categorys = getParent_cid(selectList,0L);
        //2.封装数据
        Map<String, List<Catelog2Vo>> parent_id = level1Categorys.stream().collect(Collectors.toMap(k -> k.getCatId().toString(), v -> {
            //3.每一个子类的二级分类
            List<CategoryEntity> categoryEntities = getParent_cid(selectList,v.getCatId());
            List<Catelog2Vo> catelog2Vos = null;
            if (categoryEntities != null) {
                catelog2Vos = categoryEntities.stream().map(l2 -> {
                    Catelog2Vo catelog2Vo = new Catelog2Vo(v.getCatId().toString(), null, l2.getCatId().toString(), l2.getName());
                    //查询三级分类
                    List<CategoryEntity> categoryLevel3 = getParent_cid(selectList,l2.getCatId());
                    if (categoryLevel3!=null){
                        //封装为指定格式
                        List<Catelog2Vo.Catelog3Vo> level3Catelogs = categoryLevel3.stream().map(l3 -> {
                            Catelog2Vo.Catelog3Vo catelog3Vo = new Catelog2Vo.Catelog3Vo(l2.getCatId().toString(),l3.getCatId().toString(),l3.getName());
                            return catelog3Vo;
                        }).collect(Collectors.toList());
                        catelog2Vo.setCatalog3List(level3Catelogs);
                    }
                    return catelog2Vo;
                }).collect(Collectors.toList());
            }
            return catelog2Vos;
        }));
        String s = JSON.toJSONString(parent_id);
        redisTemplate.opsForValue().set("catalogJSON",s,1, TimeUnit.DAYS);
        return parent_id;
    }

    private List<CategoryEntity> getParent_cid(List<CategoryEntity> selectList,Long parent_cid) {
        //return baseMapper.selectList(new QueryWrapper<CategoryEntity>().eq("parent_cid", v.getCatId()));
        List<CategoryEntity> collect = selectList.stream().filter(item -> item.getParentCid() == parent_cid).collect(Collectors.toList());
        return collect;
    }

    private List<Long> findParentPath(Long catelogId, List<Long> path) {
        path.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if (byId!=null&&byId.getParentCid()!=0){
            findParentPath(byId.getParentCid(), path);
        }
        return path;

    }

    private List<CategoryEntity> getChildrens(CategoryEntity root,List<CategoryEntity> all){
        //递归查找所有菜单的子菜单
        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
//            return categoryEntity.getParentCid() == root.getCatId();
            return categoryEntity.getParentCid().equals(root.getCatId());
        }).map((categoryEntity -> {
            categoryEntity.setChildren(getChildrens(categoryEntity,all));
            return categoryEntity;
        })).sorted((menu1,menu2)->{
            return (menu1.getSort()==null?0:menu1.getSort())-(menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

}
